Flat roof green roof system WALKWAYS

When planning walkways on roofs the weight of the build-up should be considered from the very beginning. During the installation of the different build-up layers the waterproofing has to be protected from damage. It is possible to install a protection mat or a drainage layer which functions as a protection layer as well, such as Elastodrain® EL 202 or Protectodrain® PD 250. The drainage of hard landscapes mostly takes place on the surface. Therefore, a sufficient slope towards the roof drains has to be allowed for. Above the drains removable terrace grills ensure that the water gets downwards and also keep the drains accessible for maintenance. As opposed to landscaped rooftops where water is to be held back and run-off is to be delayed, walkways need most of the rainwater to be quickly drained off the surface. Hence, the drainage points should allow for two levels of drainage: at the surface level and at the lower drainage level. The ZinCo product range provides the necessary systems and accessories to cater for this. The inclination of the surface layer depends primarily on the surface material. A “stilted surface layer“ does not need any slope since water can drain through the joints and standing water is not to be expected, whereas concrete or paver surfaces require a minimum inclination. Establishing a slope is not a problem, if the waterproofing and the surface have the same slope. If a slope different from the slope of the waterproofing has to be integrated into the surface, a gravel base layer is necessary. When designing a fall the connection heights need to be taken into consideration.